Re: [PATCH v2 7/7] x86/CPU/AMD: Output the AGESA version to the logs

Yazen Ghannam
2025-12-18T15:47:16Z

On Wed, Dec 17, 2025 at 03:21:17PM -0600, Mario Limonciello wrote:
> On 12/17/25 3:18 PM, Yazen Ghannam wrote:
> > On Tue, Dec 16, 2025 at 06:33:54AM -0600, Mario Limonciello (AMD) wrote:
> > > On AMD Zen platforms that are running AGESA, there is sometimes
> > > DMI additional string for the AGESA version that can be helpful when
> > > debugging an issue. If this string is found output to kernel logs.
> > >
> > > Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
> > > ---
> > > arch/x86/kernel/cpu/amd.c | 18 ++++++++++++++++++
> > > 1 file changed, 18 insertions(+)
> > >
> > > diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
> > > index c19c4ee74dd1f..8f44439d3f993 100644
> > > --- a/arch/x86/kernel/cpu/amd.c
> > > +++ b/arch/x86/kernel/cpu/amd.c
> > > @@ -1,6 +1,7 @@
> > > // SPDX-License-Identifier: GPL-2.0-only
> > > #define pr_fmt(fmt) "x86/amd: " fmt
> > > +#include <linux/dmi.h>
> > > #include <linux/export.h>
> > > #include <linux/bitops.h>
> > > #include <linux/elf.h>
> > > @@ -1406,3 +1407,20 @@ static __init int print_s5_reset_status_mmio(void)
> > > return 0;
> > > }
> > > late_initcall(print_s5_reset_status_mmio);
> > > +
> > > +#ifdef CONFIG_DMI
> > > +static __init int print_agesa_dmi_info(void)
> > > +{
> > > + const struct dmi_device *dev = NULL;
> > > +
> > > + while ((dev = dmi_find_device(DMI_DEV_TYPE_ADDITIONAL, NULL, dev))) {
> > > + if (!strncmp(dev->name, "AGESA", 5)) {
> > > + pr_info("%s\n", dev->name);
> > > + break;
> > > + }
> > > + }
> > > +
> > > + return 0;
> > > +}
> > > +late_initcall(print_agesa_dmi_info);
> > > +#endif
> > >
> >
> > The Zen check is gone. Is that intentional?
> >
>
> No it's not, it's a good catch. We don't have an AGESA version in SMBIOS
> data on pre-zen hardware.
>
> I'll add in a check like we do for print_s5_reset_status_mmio() for the next
> spin.
>
> if (!cpu_feature_enabled(X86_FEATURE_ZEN))
> return 0;
>

In that case, please consider a wrapper function that checks for Zen and
calls the two functions: AGESA and S5_RESET_STATUS.

Thanks,
Yazen